The truth is: it is dynamically linked, but against 32-Bit libraries. And since I have not yet installed any 32-Bit library, ldd doesn’t work properly. According to the readme, you should install the 32-Bit variant of libc and libncurses. Since Ubuntu is Multi-Arch, you can easily install those libs:

sudo apt-get install libc6:i386 libncurses5:i386

Now you should be able to run the Linaro toolchain on 64-Bit variants of Ubuntu.